This application claims the priority of German application 297 16 257.8, filed in Germany on Sep. 10, 1997, the disclosure of which is expressly incorporated by reference herein.
The invention relates to a stacking-disk heat exchanger, particularly an oil/coolant cooler for use in a motor vehicle, having a housing which is constructed of several stacking disks and which has connections for at least one heat transfer medium.
A stacking-disk heat exchanger of this type is known from European Patent Document EP 0 623 798 A2 in the form of an oil/coolant cooler for an internal-combustion engine. When such oil/coolant coolers are used in motor vehicles, sudden leaks could occur which resulted in the leaking-out of oil. If this leaking oil reached hot parts of the exhaust system of the internal-combustion engine, this could result in an ignition and possibly in a vehicle fire.
It is an object of the invention to provide a stacking-disk heat exchanger of the initially mentioned type which ensures a higher safety with respect to the sudden leaking of oil.
This object is achieved in that the housing is enclosed along its circumference by a protective cover consisting of an impact-resistant material. The solution according to the invention is based on the recognition that the sudden oil losses occurred particularly as the result of stone throws during the driving operation of the vehicle or the penetration of pointed objects in the event of a vehicle crash. The protective cover consisting of the impact-resistant material according to the invention reliably prevents damage to the housing and thus an emerging of oil from the housing. The protective cover can consist of a corresponding metal or of another impact-resistant material.
As a further development, the protective cover consists of a plastic material. This is a particularly advantageous development at reasonable cost which ensures reliable protection of the housing by means of simple devices.
As a further development of the invention, the protective cover consists of two shells. In a particularly advantageous manner, the two-shell design permits the subsequent mounting of the protective cover on the finished stacking-disk heat exchanger. Independently of whether the protective cover is made of one shell, two shells or several shells, according to the invention, it is detachably mounted on the circumference of the housing so that it can be mounted or demounted as required.
In a further development of the invention, both cover shells of the protective cover are provided with corresponding detent elements for the mutual connection on the circumference of the housing. In a simple manner, this achieves a form-locking interlocking of the two cover shells.
In a further development of the invention, the corresponding detent elements are molded in one piece to the two cover shells. As a result, the two cover shells can be snapped to one another without additional fastening elements in a simple manner on the circumference of the stacking-disk heat exchanger.
As a further development of the invention, both cover shells, including the respective corresponding detent elements, have an identical design. As a result, a simplified production of the protective cover is achieved because only one injection molding die is required for producing both cover shells.
As a further development of the invention, the cover shells have circumferential ribbings on their interior surfaces facing the housing which, in the mounted condition, are supported between adjacent stacking disks of the housing. This results in a supplementary form-locking securing of the cover shells on the housing.
In a further development of the invention, the cover shells are provided with reinforcing ribs on their outer circumference. This achieves an additional guarding against stone throws or the penetration of pointed objects into the stacked-disk heat exchanger.
In a further development of the invention, opposite longitudinal sides of the cover shells--viewed in the circumferential direction--are provided with concave curvatures. This results in an additional, force-locking bracing of the cover shells on the housing of the stacking-disk heat exchanger, whereby a further improved securing of the protective cover on the housing is achieved.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.